Remove apache tls-proxy sites when stopping

Currently doing a cycle of

    ./stack.sh; ./unstack.sh; ./stack.sh

fails because the leftover tls-proxy sites will cause apache startup to
fail on the second stack.sh run. So we need to disable these sites on
running stop_tls_proxy.

Change-Id: I03e6879be332289d19ca6a656f5f9f139dffff6f
Closes-Bug: 1718189
diff --git a/lib/tls b/lib/tls
index 0baf86c..0bc389b 100644
--- a/lib/tls
+++ b/lib/tls
@@ -564,6 +564,20 @@
 # using tls configuration are down.
 function stop_tls_proxy {
     stop_apache_server
+
+    # NOTE(jh): Removing all tls-proxy configs is a bit of a hack, but
+    # necessary so that we can restart after an unstack.  A better
+    # solution would be to ensure that each service calling
+    # start_tls_proxy will call stop_tls_proxy with the same
+    # parameters on shutdown so we can use the disable_apache_site
+    # function and remove individual files there.
+    if is_ubuntu; then
+        sudo rm -f /etc/apache2/sites-enabled/*-tls-proxy.conf
+    else
+        for i in $APACHE_CONF_DIR/*-tls-proxy.conf; do
+            sudo mv $i $i.disabled
+        done
+    fi
 }
 
 # Clean up the CA files